Qingyan Shi

Jiangnan University · Applied Mathematics

The dynamics of a pollen tube model with nonlocal effect and time delay is investigated in this paper. Compared with the model without delay, a double Hopf bifurcation due to the interaction of homogeneous and nonhomogeneous Hopf bifurcations can occur and quasi periodic patterns can be observed. Besides, the interaction of Turing bifurcation and s...

In this paper, we study the effect of spatial average and time delay on the dynamics of a diffusive predator–prey model under the Neumann boundary condition. Compared to the model without spatial average, the delay‐induced Hopf bifurcation at the first critical value of delay is nonhomogeneous due to the joint effects of spatial average and delay,...

In this paper, we are concerned with a reaction-diffusion model incorporating delay and nonlocal effects. The normal form of double Hopf bifurcation is derived. The diffusive model of pollen tube tip growth is discussed and numerical simulations show that spatially homogeneous and inhomogeneous periodic solutions can be both stable or connected by...

In this paper, we study the effect of time delay on the dynamics of a diffusive predator–prey model with predator-taxis under the Neumann boundary condition. The joint effect of predator-taxis and delay can lead to spatially nonhomogeneous periodic patterns via spatially nonhomogeneous Hopf bifurcations. It is also shown that there exist double Hop...

Some quantities in reaction-diffusion models from cellular biology or ecology depend on the spatial average of density functions instead of local density functions. We show that such nonlocal spatial average can induce instability of constant steady state, which is different from classical Turing instability. For a general scalar equation with spat...

Diffusion has been widely applied to model animal movement that follows Brownian motion. However, animals typically move in non-Brownian ways due to their perceptual judgment. Spatial memory and cognition recently have received much attention in characterizing complicated animal movement behaviours. Explicit spatial memory is modeled via a distribu...

Some quantities in the reaction-diffusion models from cellular biology or ecology depend on the spatial average of density functions instead of local density functions. We show that such nonlocal spatial average can induce instability of constant steady state, which is different from classical Turing instability. For a general scalar equation with...

A reaction-diffusion model is proposed to describe the mechanisms underlying the spatial distributions of ROP1 and calcium on the pollen tube tip. The model assumes that the plasma membrane ROP1 activates itself through positive feedback loop, while the cytosolic calcium ions inhibit ROP1 via a negative feedback loop. Furthermore it is proposed tha...

In this paper, we study the Hopf bifurcation and spatiotemporal pattern formation of a delayed diffusive logistic model under Neumann boundary condition with spatial heterogeneity. It is shown that for large diffusion coeffcient, a supercritical Hopf bifurcation occurs near the non-homogeneous positive steady state at a critical time delay value, a...

The stability and bifurcation of the Nicholson’s blowflies equation with nonlinear density-dependent mortality rate and delay feedback are investigated. First, we study the existence of positive equilibria and the stability of positive equilibria in the absence of delay. Then, how delay influences the stability of positive equilibria is studied. Ac...